Ships

Spaceship by ~Brenda-Starr~
Spaceship by ~Brenda-Starr~ Creative Commons 2.0 (by)

What is the future without spaceships?

In Freehauler Alcione, mighty ships of all types move between the stars, orbit planets, dock at habitats.

There are so many types of ships only the barest classification can be given here

Category

Ship functions and categories include everything from passenger liners to private recreational craft for the very wealthy, to cargo/freight merchanteers, both corporate and freehaulers, to military ships of many types (from short-range dropships and small long range patrol corvettes to huge carriers and dreadnoughts) to specialised vessels such as mining, rescue, scientific, etc.  Apart from some smaller aerodynamic types, none of these land on planets, that being the role of dedicated shuttlecraft and landers.

Drive

There are many different propulsion types (putting aside FTL for the moment).  But basically these can be divided into Rocket, Reactionless, and Exotic

Rocket

The most basic type of ship uses Newtons Third Law of Motion.  Reaction mass, such as heated plasma or charged ions, are expelled out one end at high speed.  This pushes the ship forward. Here there are two factors, thrust (the amount of mass coming out the engine, and hence the rocket’s acceleration) and specific impulse (isp) which is a fancy way to say fuel efficiency.  Generally the most fuel efficient rockets have the lowest thrust, and vice versa.

Chemical rockets combine oxygen and hydrogen, or other substances, to create a flammable mixture that pushes the rocket forward.  These have very high thrust, but very low isp (fuel economy). They are safe (if regularly well maintained), cheap, low tech (humans have used them since the days of Old Earth), can be used near space habitats, and are perfect for small short range craft like shuttles, as well as tugboats, and steering rockets on large ships. Fuel is cheap, they can use the elements  of ordinary water.  On the down side they are temperamental, all the valves and pumps can be fidgety and wear out after a while, if not regularly maintained they will go wrong at the worst possible time

Ion engines use a beam of electromagnetically accelerated charged particles. They are safe, reliable, fuel efficient, low tech, cheap and easy to use, with few or no moving parts.  On the down side, they produce only miniscule amounts of thrust.

Nuclear engines use a cheap reaction mass (say, water, or hydrogen) heated by a fission or fusion reactor and expelled at high temperature out the nozzle.  The rocket itself is similar to the chemical rocket, but the reactor and the exhaust plume is usually radioactive,  this means they can’t be used to close to habitats.  They have less thrust than chemical rockets but more than ion engines, as far as efficiency goes they are likewise intermediate.  They are popular with isolated or libertarian groups who don’t want to rely on galactic infrastructure

Torchships are a type of exceedingly powerful nuclear fission or fusion rocket that has engine output in the near terawatt to multi terawatt range.  They combine high thrust with high efficiency.   The engine output is so high (equivalent to a tactical or even strategic nuclear bomb every second) they require special shielding, cooling and so on.  Any unprotected thing on the outside of the hull would be vaporised.  They cannot be used anywhere around habitats, or other vessels, so they usually employ chemical rockets as an auxillery means of propulsion, or even a lower output (low gigawatt) nuclear rocket as a middle gear.  They are popular with groups and ideologies that don’t have access to exotic matter and don’t want to deal with Tyrusian or other alien races that supply hyper dimensional tech.  For the most part however they have long been superseded by exotic matter drives .  Their isp allows them to travel up to a couple of hundred kilometers per second maximum in realspace. Relativistic travel in realspace is impractical due to the astronomical energy requirements; it is much easier to just jump in and out of paraspace, assuming the ship has FTL capacity.

Reactionless

(to be added)

Exotic

(to be added)

FTL

While vessels that transit realspace and straight-line paraspace tend to be inorganic only, a combination of organic and inorganic is necessary for zone ships. These vary according to zone; each ship type and zone type has certain advantages and disadvantages in different zones and depends on plasticity. For example bioships are disadvantaged in realspace, more capable in paraspace and hugely suited for aetherspace. For inorganic ships it’s the opposite. Each zone requires a different type of drive to function in each zone it traverses, attuned to the laws of reality of that zone.